Bolt-threading machine



Nov. 30 1926.

A. S HOLMES BOLT THREADING MACHINE Filed June 12, 1925 2 Sheets-Sheet 1 I VVENTOR.

BY M 45,, mmz

TTORNEYS.

llllnv Nov. 30,1926. 1,608,940

-A. S. HOLMES BOLT THREADING MACHINE Filed June 12, 1925 2 Sheets-Sheet 2 N VEN TOR.

A TTORNEYS'.

Fat-sided Nov. 30, 1926.

UNITED STATES PATENT OFFICE.

BOLT-THREADING MAC NE.

Application filed June 12, 1925. Serial No. 36,658.

This invention relates to improvements in bolt threading machines, and'more particularly to a tilted, automatic bolt threading machine. It is one of the objects of the present invention to provide a bolt threading machine in which operating cams are worked against counter-weights so that if a bolt is improperly entered into a cutter or if a die head becomes clogged, the counterweight will prevent further operation of the machine so far as the particular die is concerned, without breaking or injuring any part of the machine, and permitting the continued opera tion of the machine with respect to other bolts which are being simultaneously threaded.

A further object of the invention is to pro- "Jidca bolt threading machine arranged to simultaneously thread a plurality of bolts, the parts being synchronized to ope-rate alternately or impairs, as desired.

A further object of the invention is to provide a bolt threading machine in which the front is tilted so that the work will be approximately at a right angle to the eyes of the operator to be readily visible at all times.

A further object of the invention is to pro vide a bolt threading machine constructed so that gravity is utilized in the performance of a number of operations.

A further object of the invention is the provision of a bolt threader in which the spindles are placed at an angle of thirty degrees from vertical to permit the use of selfclamping slots, to provide ample lubrication of working parts and the free washing away of chips, and to facilitate the automatic ejection of threaded bolts into a conveyor.

A further object of the invention is to pro vide a bolt threading machine which is of very simple construction, is strong and durable, and is well adapted for the purposes described. 7 y

lVith the above and other objects in view, the invention consists of the improved bolt threading machine, and its parts and combinations as set forth in the claims, and all equivalents thereof. n

In the accompanying drawing in which indicates the frame of the improved bolt threading machine in the upper portion of which. is mounted a main drive shaft ll hav ing keyed thereon a pulley 12 which is in belted connection with a source of power (not shown). A train of gears, indicated generally :by the numeral 13, receiving rotation trom a gear on the mam drive shaft 11, transmits the proper rotation to an upper shaft 1% which has keyed thereto at spaced intervals a plurality of miter gears 15, the number of said miter gears employed depending on the number of dies with which the machine is equipped. The dies are retated by shafts 16 carrying at their upper ends miter gears 17 to mesh with the aforementioned miter gears 15.

A plurality of cams 22 are carried by a lower cam shaft 21 at spaced intervals and ach cam operates a fulcrumed lever 23 arranged to ride on the edge of its cam. One end of the lever carries a weight 24, while the forward end of the lever 23 has revolubly connected. thereto a roller 25 for engagement with a block 26 slidably mounted in a portion 27 of the machine frame, it being noted that the front of the machine is in clined at approximately forty-five degrees. Connected to the front of each block 26 is a bolt holder 28, shown in detail in Fig. 5 and having a slotted front portion 29. A bolt to be threaded, designated by the numeral 30. is slipped into a holder through the slotted front portion and is retained in position by a transverse pin 31. As shown, the bolt holders 28 are of split formation and are clampingly held to the blocks 26 by transverse bolts 32 which when loosened permit the holders 28 to be slidingly adjusted with. respect to the blocks to accommodate the holders to bolts of different lengths.

Cams 22 and levers 23 are so arranged that when a lever rides over a certain portion of its cam, the weight 24 will fulcrum the forward end portion of the lever upwardly, sliding the block 26 and bolt holder 28 upwardly 7 until the end portion of the bolt enters one of the threading dies 33 immediately there above.

Threading dies of a conventional'form may be utilized, preferably of a type comprising a die head cover 34 enclosing a die head body 35 in which a plurality of chasers 36 are separably held. The die head body is formed with an elongated tubular exten sion portion 37 secured to a sleeve portion 38 of the shaft 16 whereby the die head body and chasers are revolved.

The bolt holders 28 carrying the bolts 30 are raised, as aforesaid by means of the cams 22 and weighted levers 23 operating on the sliding blocks 26, until the end portions of the bolts are engaged by the re volving chasers 36. The threading of the shank of a bolt will cause an upward feeding of thebolt, moving the bolt holder therewith until a latch pin 39 projecting from the block 26 engages a die head latch 40 and thereby lifts the die head cover 34 above the chasers 33 and as the same are spring urged, they will then separate and release a threaded bolt. The bolt holder and sliding block then drop back, by force of gravity,-

against the bolt starting lever 23. The finished bolt 30 is then manually ejected from its bolt holder and the bolt holder is then ready to receive another bolt and repeat the operation.

vVhen the finished bolt 30 is ejected from the-bolt holder. it falls into a trough 41 and from thence it is conveyed to a suitable container by a conveyor belt 42. The conveyor belt runs over a pair of sprocket wheels 43, one of which is driven by a pair of miter gears 44, in connection by means of a shaft 45, sprocket gear-s46 and a chain 47 with the lower cam shaft 21 which is driven by means later to be explained.

A plurality of cams 48 are carried by an upper cam shaft 49 at spaced intervals. there being one of said cams for each threading (lie. Pivotally mounted above each of the cams 48 is a die closing lever having a weighted inner end 51, each die closing lever being arranged to ride on its cam. The cams are constructed so that immediately after the diehead cover has been raised and the bolt released, the bearing portion of the lever 50 will ride on a flattened portion of its cam whereby the weighted lever will exert a pressure on the top of the die head cover and meshes with the return it to normal position enclosing the chasers in closed position.

A cone pulley 18 is mounted on the drive shaft 11, and a belt 19 carried by said pulley 18 and by a lower cone pulley 20 mounted on stud shaft 21, transmits power from the drive shaft 11 to the lower cam shaft 21 by means of a gear 52 carried by the stud shaft 21, a gear 53 carried by the lower cone shaft and an intermediate gear 54 therebetween. By shifting the belt 19 with respect to the cone pulleys a change in the speed of rotation of the cam shaft can be effected. Motion is transmitted to the upper cam shaft 49 by means of a gear 55 carried thereby engaging a gear 56 which in turn gear 52.

In order to cut left hand threads on bolts, it is only necessary to change the chasers 36 of the dieheads and shift a lever 57 connected to the train of gears 13 to reverse the movement of the shaft 14.

Lubrication for the cutting mechanism is afforded by a tank 58 in the lower portion of the machine which is filled with a suit able cutting fluid. The cutting fluid is pumped from the tank into a pipe 59 by a geared pump 60 which is driven by power taken from the main drive shaft 11 through pulleys 61 and 62 and a belt 63 connecting the same. The cutting fluid is forced through the pipe 59 and an upper vertical distributor pipe 64 communicating with each cutting die. As shown in Fig. 4 the portion 37 of each cutting die is tubular and the shaft extension 38 is surrounded by a collar 65 receiving the pipe 64. Hence the cutting fluid is free to flow through the vent 66 of the pipe 64 and into the channel 67 of the shaft portion 38. From thence the fluid flows freely through the portion 37 and lubricates the chasers 36 and the work.

Obviously, in operation, the operator places bolts in the bolt holders and the weighted levers 2.3 and cams 22 will force the bolts into the die heads. As the die heads cut the threads, the bolts and holders are pulled inwardly until the die head latches are struck causing the bolts to be released. The bolt holders then drop back to starting positions and the bolts are ejected. Also the die head covers are automatically replaced. 7

.The improved machine is especially advantageous in that the cams act only against counterweights and if a bolt is imperfectly entered the chasers cannot be broken nor can a clogged die head he strained.

From the foregoing description itfwill be seen that the improved bolt threading machine is of very simple and novel construction, and is well'adapted for the purposes set forth.

What I claim as my inventionis 1- 1. A bolt threading machine, comprising Hill all

a frame, a bolt holding member mounted therein, a cutting die thereabove, a pivoted lever adjacent said bolt holding member, means for pivoting said lever whereby it will engage said bolt holding member and force it upwardly toward the cutting die, and cam means for pivoting said lever to an inoperative position wherein its pressure against the bolt holding member is relieved to ermit a free gravitation of the bolt holding member to normal position.

2. A bolt threading machine, comprising a frame, a bolt holding member slidably mounted therein, a cutting die thereabove, a pivoted lever freely engaging said bolt holding member, and a cam; for pivoting the engaging end portion of lever upwardly to raise the bolt holding member at certain periods, and entirely disengaging the lever from the bolt holding member at other periods to cause the gravitation of the bolt holding member.

A bolt threading machine, comprising a frame, a bolt holding member slidably mounted therein, a cutting die thereabove, a cam actuated. lever freely engaging the bolt holding member and arranged to push it upwardly toward the cutting die to permit the same to engage a bolt carried by the bolt holding member, means for causing the cutting die to release its work, and cam means engaging said lever for relieving the pressure exerted by the lever on the bolt holding member to per nit the same to gravitate to normal position.

l. A bolt threading machine, comprising a frame, an adjustable bolt holding member mounted therein, a cutting die thereabove, a pivoted lever adjacent said bolt holding member, means for pivoting said lever whereby it will engage said bolt holding member and force it upwardly toward the cutting die, and cam means engaging said lever for pivoting it to a position wherein its pressure against the bolt holding member is relieved to permit a gravitation of the bolt holding member to normal position.

5. A bolt threading machine, comprising a frame, a bolt holding member slit ably mounted therein, a releasing cutting die thereabove, a cam actuated and weighted lever freely en 'aging the bolt holding member and arranged to push it upwardly toward the cutting die to permit the same to engage a bolt carried by the bolt holding member, means for automatically causing the cutting die torelease its work, cam means operating on said lever for relieving the pressure exerted by the same on the bolt holding member to permit it to gravitate to normal position, and a cam actuated and weighted lever controlling the releasing cutting die.

6. A bolt threading machine, comprising a frame, a bolt holding member slidably mounted therein, and formed with a projecting latch pin, a cutting die thereabove formed with separable chasers enclosed by a movable die head cover, said die head cover having a latch, a fulcrumed lever adjacent the die holding member, means for fulcrnming said lever to engage the bolt holding member to lift the same, the die head cover latch being engaged and moved by said latch pin upon a predetermined lift of the bolt holding member, a fulcrumed lever adjacent the die head cover, and means for fulcruming said last mentioned lever to engage the die head cover and return it to normal position.

7. A bolt threading machine, comprising a frame, a bolt holding member slidably mounted therein, a revolving cutting die thereabove formed with separable chasers enclosed by a movable die head cover, a weighted lever pivotally carried by the frame and arranged to engage the bolt holding member, a cam engaging and pivoting said lever, a latch pin carried by the bolt holding member to engage and lift the die head cover, a weighted lever pivotally mounted above the die head cover, and a cam engaging and pivoting the last men tioned lever to cause it to exert a pressure on said die head cover.

8. A bolt threading machine, comprising a frame, a bolt holding member slidably mounted therein, a latch pin carried by and extending upwardly from the bolt holding member, a revolving cutting member above said bolt holding member and comprising separable chasers normally enclosed by a die head cover, a weighted lever pivotally carried by the frame and arranged to engage the bolt holder member to lift the same toward the cutting member, a cam engaging and operating said lever, said latch pin en gaging and lifting the die head cover upon a predetermined movement of the bolt holding member, a weighted lever pivotally mounted above the die head cover, a cam engaging and pivoting the last mentioned lever to cause it to exert a pressure on the raisee die head cover to return it to normal position, means for lubricating the cutting member, and means for operating said cams and cutting member.

In testimony whereof, I aflix my signature.

ARTHUR S. HOLMES. 

